Law of conservation of mass

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What is the Law of Conservation of Mass?

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The Law of Conservation of Mass states that mass is neither created nor destroyed in a chemical reaction; the total mass of the reactants equals the total mass of the products.

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What does a coefficient in a chemical equation represent?

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A coefficient in a chemical equation represents the number of moles of a substance involved in the reaction.

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How do you balance a chemical equation?

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To balance a chemical equation, adjust the coefficients of the reactants and products to ensure that the number of atoms of each element is the same on both sides of the equation.

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What are reactants in a chemical reaction?

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Reactants are the starting substances in a chemical reaction that undergo change to form products.

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What is a product in a chemical reaction?

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A product is a substance that is formed as a result of a chemical reaction.

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What is an example of a physical change that is not a chemical reaction?

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Melting of ice is an example of a physical change that is not a chemical reaction.

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Why is it incorrect to say that gases produced in a reaction do not need to be accounted for?

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It is incorrect because gases have mass and contribute to the total mass of the products; they must be accounted for in the Law of Conservation of Mass.

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What is the significance of balancing chemical equations?

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Balancing chemical equations is significant because it ensures that the Law of Conservation of Mass is upheld, reflecting the actual quantities of reactants and products.

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What is the balanced equation for the combustion of propane (C3H8)?

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The balanced equation for the combustion of propane is C3H8 + 5O2 -> 3CO2 + 4H2O.

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What is the difference between a chemical change and a physical change?

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A chemical change results in the formation of new substances with different properties, while a physical change does not alter the chemical composition of a substance.